mirror of
https://github.com/permissionlesstech/bitchat.git
synced 2026-07-24 23:45:18 +00:00
84d315e62d
* Bridge dedup keys on a content-derived stable mesh message ID Public mesh messages carry no message ID on the BLE wire, so every non-origin device minted a fresh UUID and the bridge's m-tag dedup only matched on the origin device: duplicate bridged rows, misattributed "across the bridge" counts, redundant downlink rebroadcasts, and an m-tag spoof vector (an attacker could claim a victim's message ID). Every device now derives the same stable ID from the signed wire fields (sender ID + ms timestamp + trimmed content, SHA256/32 hex) via the new MeshMessageIdentity — zero BLE wire change. The bridge event's m tag carries the origin coordinates ["m", senderIDHex, timestampMs] and receivers recompute the key from those plus the event's own content instead of trusting a claimed ID; old-format/absent tags fall back to the event ID as before. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> * Fix mixed-version message loss: m tag leads with the derived stable ID The previous layout (["m", senderIDHex, timestampMs]) broke v1.7.0 receivers: their parser takes m[1] unconditionally as the timeline dedup key whenever the tag has >= 2 elements, so every bridged message from a new-version sender keyed on the CONSTANT sender hex and inject-dedup dropped all but the first. The tag is now ["m", <derived stable ID>, senderIDHex, timestampMs]: old parsers get a per-message-unique m[1] (exactly today's semantics), while the new parser recomputes the ID from elements 2-3 plus the event's own content and never trusts element 1, keeping the recompute-don't-trust property. Also: - Soften the overstated security claim in MeshMessageIdentity and the BridgeService classify comment: forging a chosen ID onto different content is infeasible, but all three hash inputs are cleartext on the radio, so identical-content front-running by a radio-local attacker remains possible (no worse than the unbridged mesh). - Fix the stale archivedEchoKeys rationale: re-synced copies of others' messages now carry the derived stable ID (insert-by-ID catches them); the content key remains for echo--prefixed archive rows + self echoes. - Tests: old-parser semantics on the new tag (m[1] per-message-unique and equal to the derived ID) and a forged-m[1] event that cannot pre-poison a genuine message's dedup slot. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> --------- Co-authored-by: jack <jackjackbits@users.noreply.github.com> Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>
Test Harness Guide
This test suite uses an in-memory networking harness to make end-to-end and integration tests deterministic, fast, and race-free without touching production code.
In-Memory Bus
- File:
bitchatTests/Mocks/MockBLEService.swift - Registry/Adjacency: Global
registrymapspeerIDto aMockBLEServiceinstance;adjacencyrecords simulated links between peers. - Setup: Call
MockBLEService.resetTestBus()insetUp()to clear state between tests. - Topology: Use
simulateConnectedPeer(_:)andsimulateDisconnectedPeer(_:)to add/remove links.connectFullMesh()helpers in tests build larger topologies. - Handlers: Tests can observe data via
messageDeliveryHandler(decodedBitchatMessage) andpacketDeliveryHandler(rawBitchatPacket). - De‑duplication: A thread-safe
seenMessageIDsprevents duplicate deliveries during flooding/relays.
Broadcast Flooding
- Flag:
MockBLEService.autoFloodEnabled - Intent: When
true, public broadcasts propagate across the entire connected component (ignores TTL for reach) while still de‑duping to prevent loops. - Usage: Enabled in Integration tests (
setUp) to simulate large-network broadcast; disabled in E2E tests to keep routing explicit and verify TTL behavior (seePublicChatE2ETests.testZeroTTLNotRelayed).
Rehandshake Flow (Noise)
- Why: The legacy NACK recovery path was removed; recovery now relies on Noise session rehandshake after decrypt failure or desync.
- Manager:
NoiseSessionManagermanages per-peer sessions. - Pattern: On decrypt failure, proactively clear the local session and re-initiate a handshake. The peer accepts and replaces their session.
- Test:
IntegrationTests.testRehandshakeAfterDecryptionFailure- Corrupts ciphertext to induce a decrypt error.
- Calls
removeSession(for:)on the initiator’s manager beforeinitiateHandshake(with:)to avoidalreadyEstablished. - Verifies encrypt/decrypt succeeds post-rehandshake.
Tips
- Determinism: Add small async delays only where handler installation/topology changes could race the first send.
- Scoping: Keep
autoFloodEnabledtoggled only within Integration tests; always reset intearDown()to avoid cross-test contamination. - Direct vs Relay: Private messages target a specific peer when adjacent; otherwise they are surfaced to neighbors for relay and, if known, also delivered to the target.
Quick Start
- Create nodes and connect them:
let svc = MockBLEService(); svc.myPeerID = "PEER1"svc.simulateConnectedPeer("PEER2")
- Observe messages:
svc.messageDeliveryHandler = { msg in /* asserts */ }
- Enable broadcast flooding for Integration suites only:
MockBLEService.autoFloodEnabled = true